Abstract
Helium undergoes an amazing transition at low temperature to a frictionless fluid called a superfluid. The Nobel Prize in Physics was awarded in 1996 to the group at Cornell University which discovered suprfluidity in 3He. The common isotope of helium, 4He, goes through the superfluid transition at 2.2 degrees above absolute zero. The rare isotope of helium, 3He, goes through the transition near the much colder temperature of one thousandth of a degree Kelvin. 3He has other cool properties which have been the object of my research. I will discuss what is special about the two isotopes of helium and how we make it so cold, and show how this relates to my past and present research on superfluidity and ideal two-dimensional gases.